My parents are currently looking for a suitable spouse for me and insist I speak to any potential spouse before getting to a decision. This is the case even from the man’s side as everyone thinks we should get to know each other before making such a big decision. I think along the same lines too; however, I don’t feel like it’s right to engage in casual conversations with the opposite sex and I’m afraid I may be doing something wrong. Please advise me as to what to do and how best to act in such a situation.

Its a good thing to try getting to know your potential spouse by talking to him with the permission of your parents ofcourse, but there are limits to this.
All the experts of law confirm to the fact that if the intention is truly for marriage purposes and not one that leads to any kind of lust or desire through words or actions is allowed.
You should also remember that one can never be able to really know a person as well unless one lives with a person under a roof, or even when one gets committed like reciting a temporary marriage seegha so that one could freely talk.
The solution is either be careful in what you converse by not going too far in your relationship through your words and expressions, or request for a temporary Aqd of Nikah to be recited so you can just talk and get to know each other. If at all you try freely conversing, you might fall in a forbidden act which is a sin.
You can remind your potential spouse of what Islam says about relationships with Na mahram before the Nikah and get to know him a little through a couple of.meetings and maybe asking your questions through media or something without getting carried away. In the process you can know if he holds it important to follow the shairat too. If you are careful, inshAllah you will not fall into a forbidden act.